Mobile crane



May 15, 1945. Re. LE TOURNEAU MOBILE CRANE Filed. Jan. 22, 1944 2Sheets-Sheet l iNvENToR R.G.ll'7urzzaau.

' A'rrrs y 1945- R. G.'LE TOURNEAU Q 2,375,800

MOBILE CRANE Filed Jan. 22, 1944 2Sheets-Sheet 2 INVENTYOR WWI;

A TTYS R. G. LeTe'aurneaaa Patented May 15, 1945 MOBILE CRANE Robert G.-Le Tourneau, Peoria, 11L, assignor to R. G. Le Tourneau, Inc., Stockton,Calii?.,v a corporation of California Application January 22, 1944,Serial No; 519,327

11 Claims.

This invention relates in general to an imroved mobile or portablecrane, and in particular the invention is directed to, and it is anobject to provide, a self-propelled mobile crane which includes afoldable mast and boom assembly whereby for transport of the crane fromplace to place said mast and boom assembly may be folded so as to notrequire any great head clear- .ance.

A further object of this invention is to provide a crane as above whichis self-erecting; the crane including an engine actuated winch, andthere being operating connections between said winch and the mast andboom assembly whereby to raise said assembly from a folded position toan erect position.

An additional object is toprovide a crane as above in which saidoperating connections include a unique cable system operative to controllowering and folding movement of the mast and boom assembly, and tocause unfolding and erection thereof.

Another object of the invention is to provide a crane which comprises anengine propelled vehicle, a normally upstanding mast, means pivotingsaid mast at its lower end on. the vehicle for swinging movement to alowered position, releasable holding means normally preventing suchlowering movement of the mast, a normally outwardly projecting boompivoted in connection with the upper end of the mast for downwardfolding movement to a lowered position against the mast, releasableholding means normally preventing such downward folding-movement of theboom, and engine actuated means connected with said mast operative tocontrol lowering movement of said mast from an, erected position to alowered position, and to raise the mast to said erected position fromsaid lowered position.

A still further object of this invention is to provide a crane, as inthe preceding paragraph,

in which said engine actuated means is operative.

to control folding of the boom after the mast is in said loweredposition and said boom holding means released, and to raise said boom tonormal position for resetting of said boom holding means prior toerection of the mast.

A further object of the invention is to provide a simple and inexpensivedevice, and yet one which is exceedingly eiiective for the purpose forwhich it is designed.

These objects I accomplish by means of such structure and relativearrangementof parts as will fully appear by a perusal of the followinspecification and claims,

In the drawings similar characters of reference indicate correspondingparts in the several views:

Figure 1 is a side elevation of the crane showing, in full. lines, themast and boom assembly erected, and showing, in broken lines, said"assembly in partially lowered position.

Figure 2 is a side elevation of the crane taken from the side op ositeFig. 1, showing the mast fully lowered; the boom being shown in fulllines in a artially folded position, and in broken lines in a fullyfolded position.

Figure 3' is a fragmentary rear end view of the crane.

Figure 4 is a fragmentary plan view of the carriage and control braceunit.

Figure 5 is a diagrammatic view of the cable system.

Referring now more particularly to the characters of reference on thedrawings, the crane comprises an elongated horizontal body-forming beamI of substantial length, which is disposed adjacent but clear of theground. At its rear end thebody l includes a horizontal, transverselyextending rear axle housing 2 in rigid relation;

is connected at its forward end by draft means,

shown in part at 4, with the rear end of a'tractor, indicated generallyat 5, and which is here shown as a two-wheel type tractor having anoperator's seat 8 disposed adjacent but ahead of the yoke 3. The tractor5 is connected to the yoke 3 in vertically inflexible but horizontallysteerable relation.

A mast, indicated generally at I, normally upstands from thebody Iadjacent its rear end and is pivoted on the wheel axles between thewheels and housing 2, as at P. Said mast comprises a. pair' oftransversely spaced, upwardly converging legs 8, and another pair ofcorresponding legs 9 which are connected at' their lower ends with thecorresponding ends of legs 8' and thence extend upwardly in converging"relation to each other but in forwardIy' diverging relation to the legs8'. At their upperends thelegs 8 and 9 are connected in rigid relationby a cage-like bracing assembly or skeleton head [0. Below the head H]the legs 8 and 9 are connected by suitable bracing, as

shown.

The mast I is fitted at its upper end with a rearwardly projectingnormally substantially horizontal boom II which comprises upper andlower pairs of transversely spaced arms, indicated generally at I2 andI3 respectively, said arms projecting outwardly in converging relation.At their outer ends the arms l2 are fixedly secured together, and attheir inner, spaced apart ends said arms are connected in rigid relationby bracing Ila. The lower arms I3 of the boom, II are pivotallyconnected at their inner ends, as at I4, at transversely alined points,in connection with corresponding portions of the head I0, whereby theboom II can fold downwardly into engagement with the mast I. However,such downward movement is normally prevented by means of removable pinsI5 which connect the inner ends of boom arms I2 with correspondingportions of the head I0. When the pins I5 are in place, the boom II isrigidly secured in outwardly and rearwardly projecting relation to themast I.

The mast l is normally maintained in vertical or upright position bymeans of a pair of rigid braces I6, which are pivotally connected, as atI1, to the front of corresponding legs 9 intermediate the ends of thelatter; the braces I6 extending forwardly and downwardly in convergingrelation to fixed but pivotal connection at their lower ends with acarriage, indicated generally at I8. The carriage I8 includes a rollerI9 which rides on top of the body I, and opposed, laterally projectingtrunnions 20 which normally seat in forwardly and horizontally openingyokes or cradles 2| fixed on and upstanding from the body I, intransversely spaced relation. Escape of said trunnions from said yokesis normally prevented by means of removable cross pins 22 which extendthrough the legs of said yokes and intersect the opening thereof infront of said trunnions.

As is evident, removal of cross pins 22 will permit the carriage I8 torun forward on the body I,

with resultant forward and downward swinging movement of the mast I tothe lowered position shown in Fig. 2, and in which position the upperend of the mast engages and is supported by a shock absorber stop 23fixed on and upstanding from the top of draft yoke 3, With the mast inlowered position, as in Fig. 2, the pins I5, at the inner end of theboom l I, are accessible to the operator and uponwithdrawal of said pinsthe boom can be folded downwardly against the lowered mast, to a foldedposition, as shown in broken lines in Fig. 2.

Lowering of the mast and folding of the boom is controlled by a cablesystem which is also operative to unfold the boom and to raise the mastto an erected position; such cable system comprising the following:

A power winch, indicated generally at 24, is mounted on the rear end ofthe tractor within the yoke 3, said power winch including a pair ofcable drums, indicated at 25 and 26, respectively, said drums beingselectively operable by the driver 'of the tractor. The power winch 24is of such type that the paying out of the cables from the drums iscontrolled by an internal, operator regulated brake (not shown).

. A cable 21 leads from the drum 25 through a fairlead assembly,indicated generally. at 28, mounted on one side of the yoke 3, and fromsaid fairlead assembly the cable .21 extends. down: wardly and about afixed sheave 28a on'the lower end of yoke 3. From, the sheave 2811 cable21 extends rearwardly along and adjacent the body I to and about asheave 29 fixed in connection with the body I adjacent its rear end, andthence the cable includes a forwardly extending loop 30 which passesintermediate its ends about a sheave 3| fixed in connection with andprojecting rearwardly from the carriage I8; the cable passing from saidloop about another sheave 32 on the body alongside of sheave 29 and thenextends upward through the mast I. At a point adjacent the upper end ofthe mast, the cable 2'! turns about a sheave 33 and passes rearwardlythrough the boom and over a swinging sheave'34 depending from the outerend of said boom. From the swinging sheave 34 the cable depends in blockand tackle relation to a sheave 35 included in a lifting hook unit 36.At the rear end the crane body includes an eye 31 into which the hook 36is adapted to be engaged preparatory to lowering of the mast 1.

Another cable 38 leads from the drum 26 of winch 24 through a fairleadassembly, indicated generally at 39, secured on the corresponding sideof yoke 3. From the fairlead assembly 39 cable 38 extends rearwardly andupwardly over guide sheaves 40 fixed in th skeleton head Ill of the mastand thence continues and passes over a sheave 4I fixed in the rear endportion of the boom I I some distance above the pivots I4. After passingabout the sheave 4I the cable 38 extends forwardly and over anotherguide sheave 42 in head I0 and thence is reeved, as a block and tackleT, between a sheave 43 on the upper end of yoke 3 and a sheave 44 in thehead I0, being dead-ended to the frame of sheave 43, as at 45.

In order to lower the mast I and to fold the boom II from normaloperative position, the following operations take place:

The hook unit 36 is first lowered and engaged with eye 31, and then thecross pins 22 are removed from the yokes 2|. Thereafter, drum 26 of thewinch 24 is operated to wind in the cable 38, which results inshortening of the block and tackle T and forward and downward swingingmovement of the mast. In order to prevent the mast from falling forwardtoo rapidly, the cable 21 is simultaneously retained relatively taut andpaid out at the desired speed, which controls forward movement of thecarriage I8. It will thus be seen that the operator, by winding in cable38 onto drum 26 and paying out cable from drum 25 at a controlled rate,can lower the mast I with nicety.

After the mast reaches its lowered position in engagement with the shockabsorbing stop 23, the operator locks drum 2G and then withdraws thepins 25 at the inner end of boom II. When said pins have been withdrawnthe operator again takes his position on the tractor and slowly pays outthe cable 38 from the drum 26, which permits the projecting boom II togradually fold rearwardly and downwardly until it engages the loweredmast, as shown in dotted lines in Fig. 2. As the boom folds downwardly,the resultant slack in cable 21 is wound onto drum 25.

' To unfold the boom and erect the mast, the above procedure is merelyreversed.

From the foregoing description it will be readily seen that I haveproduced such a device as substantially fulfills the objects of theinvention as set forth herein.

While this specification sets forth in detail the present and preferredconstruction of the device, still in practice suchdeviations from suchdetail may be resorted to as do not form a departure from the spirit ofthe invention, as defined by the appended claims.

i 1 Having'thus described'my invention, .what'I claim .as new and usefuland desire to secure by Letters Patent is:

1. A crane comprisimg a longitudinally extending body supported formovement along the ground, a mast normally upstanding from the body,means pivoting the mast in connection with thebody for downward swingingmovement to a lowered position, releasable holding means normallypreventing swinging movement of the mast, a boom normally projectingoutwardly from the lectively permit the boom to drop to folded positionor to pull it to its normal extended position when the pin is removed.

2. A crane comprising a longitudinally extending wheel-supported bodyconnected in draft relation with a tractor including an engine actuatedwinch, the winch including multiple cable drums, a mast normallyupstanding from the rear end portion of the body, means pivotingthe mastin connection with the body for forward and downward swinging movementto a lowered position, releasable holding means normally prevent-ingsuch swinging'movement of the mast, a boom normally projecting outwardlyfrom the upper end portion of the mast, means pivoting the boom toconnection with the mast for downward folding movement, other releasableholding means normally preventing folding of the boom, and a cablesystem including a cable leading from each drum of the winch to the mastand boom assembly, said cable system being arranged so that one cable isoperative to control swinging of the mast to a lowered position andfolding movement of the boom, and the other cable is operative to raisethe mast from a lowered to an erected position.

3. A crane as in claim 2 in which said one cable is arranged to effectunfolding movement of the boom when the mast is in said loweredposition.

4. A crane comprising a longitudinally extending wheel-supported bodyconnected in draft relation with a tractor including an engine actuatedwinch, said winch having a pair of selectively controlled cable drums, amast normally upstanding from the rear end portion of the body, meanspivoting the mast in connection with the body for forward and downwardswinging movement to a lowered position, releasable holding meansnormally presenting such swinging movement of the mast, a boom normallyprojecting outwardly from the upper end portion of the mast, meanspivoting the boom in connection with the mast for downward foldingmovement, other releasable holding means normally preventing folding ofthe boom, and a cable system including a cable leading from each drum ofthe winch, one cable leading from the winch at an upward and rearwardincline over a guide on the mast to engagement with the boom above itspivot, and the other cable leading from the winch to the mast inerecting relation thereto.

5. A crane as in claim 4 in which said one cable passes over and about asheave on the boom, then extends forwardly over another guide on '20means connected with the boom operable to sethe. mast, and thence isformed 'a's' 'a block and tackle unit which'extends at a forward anddownward incline to connection with the body some distance ahead of themast. Y

6. A-crane comprising a longitudinally extending wheel-supported bodyconnected in draft relation with a tractor including an engine actuatedwinch, said winch having a pair of selectively controlled cable drums, aboom supporting mast normally upstanding from the rear end portion ofthe body, a brace pivotally connected to the mast intermediate its endsand extending at a forward and downward incline, a carriage supported onand adapted-to move'alongthe body ahead of the mast, the brace beingpivotally connected at its lower end-to the carriage, "releasable meansnormally preventing movement of. the carriage, a cable leading from onedrum of the winch rearwardly and about a sheave fixed on the body totherear of said carriage and thence extending forwardly toengagementwith the latteiyand a separate cable leading from the other drum of thewinch rearwardly and upwardly to engagement with the mast adjacent itsupper end. i

'7. A crane comprising a longitudinally extending Wheel-supported bodyconnected in draft relation with a tractor including anengine actuatedwinch,said winch having a pair of seleccarriage, a cable leading fromone drum of the winch rearwardly and about a sheave fixed on the body tothe rear of said carriage and thence extending forwardly to engagementwith the latter, and a separate cable leading from the other drum of thewinch rearwardly and upwardly to engagement with the mast adjacent itsupper end; said first named cable passing about a sheave fixed on thecarriage, then extending rearwardly and about another sheave fixed onthebody, and thence leading up to the mast, over a guide sheave, and outthe boom to provide the lift cable of the crane.

8. A crane comprising a wheel-supported, selfpropelled vehicle includinga power winch having a pair of separate cable drums, a mast normallyupstanding from the vehicle some distance from the winch, the mast beingpivotally mounted in connection with the vehicle for forward swing ingmovement to a lowered position, a carriage winch, releasable holdingmeans between the mast and boom normally preventing folding of thelatter, and a separate cable leading from the other drum upwardly over aguide on the mast, about a direction changing sheave on the inner endportion of the boom above its pivotal axis,

'and thence being anchored in relation to the mast --to exert a loweringforce thereon.

,l'EBJ end and being pivotally mounted thereon for forward swingingmovement to a lowered position, the boom being foldable against themast, swinging of the mast and folding of the boom,

releasable means normally preventing a pair of cables adapted to runfrom said drums,

vguide means for said cables on the body adjacent its forward end, onecable leading from said guide means to the mast in lowering relationthereto, and the other cable leading from said guide means to the mastin erecting relation thereto.

10. A crane comprising a longitudinally extending body havingtransversely spaced support ing wheels at its rear end and including adraft member at its front end, said member being adapted for connectionwith a tractor having a multiple drum power winch, a mast and boomassembly upstanding from the body adjacent its rear end and beingpivotally mounted thereon for forward swinging movement to a loweredposition, the boom being foldable against the mast, releasable meansnormally preventing swinging of the mast and folding of the boom, a pairof cables adapted to run from said drums,

' guide means for said cables on the body adjacent its forward end, onecable leading from said guide means to the mast in lowering relationthereto, and the other cable leading from said guide means to the mastin erecting relation thereto; said one cable being operative to controlfolding, and to eflect unfolding of, the boom when the mast is in saidlowered position.

11. A crane comprising a longitudinally extending body with a power unitat one end thereof, which power unit includes a dual drum power winch, amast pivotally mounted on the body in spaced relation to the power unit,a boom extending outwardly from said mast, cable means engaged with onedrum of the winch and connected with the upper end of the mast andoperable to pull the mast from vertical to inclined position, separatecable operated means associated with the mast to lift it from inclinedto vertical position and such latter means including a cable operablyconnected with the other drum and extending thence through operableconnection with said lifting'means, thence up and over the top of themast and thence out to the outer end of the boom, a block and tackleelement on the outer end of said cable forming the lift for the crane,and means for temporarily anchoring the latter element to said body andto then permit such second cable to be gradually paid out from the drumas the mast is being lowered through the medium of the other drum andcable, whereby to control the speed of lowering of the mast.

ROBERT G. LE TOURNEAU.

